Method, apparatus and system for image projection lighting

ABSTRACT

A central controller and a number of image projection lighting devices (“IPLD”), a type of multiparameter light, are interconnected by an enhanced performance communications path that is capable of simultaneously carrying different digital signals on various bidirectional channels, such as various content signals, including continuous video and/or audio, in digital form on respective content transfer channels, a command signal on a control channel, and a control or content signal in digital form on an auxiliary channel. In accordance with commands transmitted from the central controller over the control channel, content signals may be sent from any of the IPLDs to any other of the IPLDs, or from the central controller to any of the IPLDs, or from any of the IPLDs to the central controller. The IPLDs have respective unique device addresses, and the control channel, the auxiliary channel, and the content transfer channels also have respective unique channel addresses.

CROSS-REFERENCE TO RELATED APPLICATION

This patent document is a continuation-in-part of and claims the benefitof U.S. patent application Ser. No. 10/002,708, filed Nov. 1, 2001, nowU.S. Pat. No. 6,459,217, which is a division of U.S. patent applicationSer. No. 09/394,300, filed Sep. 10, 1999 (now U.S. Pat. No. 6,331,756,issued Dec. 18, 2001), all of which hereby are fully incorporated hereinin their entirety by reference thereto.

Notice: More than one reissue application has been filed for the reissueU.S. Pat. No. 6,605,907. The reissue application numbers are Ser. Nos.11/199,548 (the present application), 12/852,799, and 13/292,162.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to lighting systems that are digitallycontrolled and to the light fixtures used therein, and more particularlyto such lighting systems as well as to multiparameter lights that havean image projection lighting parameter and a camera and that are usefulin such lighting systems.

2. Description of the Related Art

Lighting systems are formed typically by interconnecting many lightfixtures by a communications system and providing for operator controlfrom a central controller. Such lighting systems may containmultiparameter light fixtures, which illustratively are light fixtureshaving individually remotely adjustable parameters such as beam size,color, shape, angle, and other light characteristics. Multiparameterlight fixtures are widely used in lighting industry because theyfacilitate significant reductions in overall lighting system size andpermit dynamic changes to the final lighting effect. Applications andevents in which multiparameter light fixtures are used to greatadvantage include showrooms, television lighting, stage lighting,architectural lighting, live concerts, and theme parks. Illustrativemultiparameter light devices are described in the product brochureentitled “The High End Systems Product Line 2001” and are available fromHigh End Systems, Inc. of Austin, Tex.

Prior to the advent of relatively small commercial digital computers,remote control of light fixtures from a central controller was done witheither a high voltage or low voltage current; see, e.g., U.S. Pat. No.3,706,914, issued Dec. 19, 1972 to Van Buren, and U.S. Pat. No.3,898,643, issued Aug. 5, 1975 to Ettlinger. With the widespread use ofcomputers, digital serial communications over wire was widely adopted asa way to achieve remote control; see, e.g., U.S. Pat. No. 4,095,139,issued Jun. 13, 1978 to Symonds et al., and U.S. Pat. No. 4,697,227,issued Sep. 29, 1987 to Callahan. In 1986, the United States Instituteof Theatre Technology (“USITT”) developed a digital communicationssystem protocol for multi-parameter light fixtures known as DMX512.Basically, the DMX512 protocol consists of a stream of data which iscommunicated one-way from the control device to the light fixture usingan Electronics Industry Association (“EIA”) standard for multipointcommunications know as RS-485.

A variety of different types of multiparameter light fixtures areavailable. One type of advanced multiparameter light fixture which isreferred to herein as an image projection lighting device (“IPLD”) usesa light valve to project images onto a stage or other projectionsurface. A light valve, which is also known as an image gate, is adevice such as a digital micro-mirror (“DMD”) or a liquid crystaldisplay (“LCD”) that forms the image that is projected. U.S. Pat. No.6,057,958, issued May 2, 2000 to Hunt, discloses a pixel based goborecord control format for storing gobo images in the memory of a lightfixture. The gobo images can be recalled and modified from commands sentby the control console. U.S. Pat. No. 5,829,868, issued Nov. 3, 1998 toHutton, discloses storing video frames as cues locally in a lamp, andsupplying them as directed to the image gate to produce animated andreal-time imaging. A single frame can also be manipulated throughprocessing to produce multiple variations. Alternatively, a videocommunication link can be employed to supply continuous video from aremote source.

U.S. Pat. No. 5,828,485, issued Oct. 27, 1998 to Hewlett, discloses theuse of a camera with a DMD equipped light fixture for the purpose offollowing the shape of the performer and illuminating the performerusing a shape that adaptively follows the performer's image. The camerataking the image preferably is located at the lamp illuminating thescene in order to avoid parallax. The image can be manually investigatedat each lamp or downloaded to some central processor for this purpose.This results in a shadowless follow spot.

BRIEF SUMMARY OF THE INVENTION

While the type of light fixture that provides a shadowless follow spotfunction and while the type of light fixture that stores imagesinternally for projection have value in the lighting industry, thesetypes of light fixtures and/or the lighting systems in which theyoperate all limit the operator of the lighting system to carrying outimage projection operations on the basis of individual light fixtures.Moreover, having to store images at the light fixture is very limitingto the user of the device, since the operator must upload images to thelight fixture from a computer before placing the light fixture intoservice.

These and other disadvantages of the prior art are overcome in one ormore embodiments of the present invention by supporting two or morechannels of content in digital form, including content such as imagecontent, over one communications path for projection by multiple IPLDsin a lighting system, or by supporting a command channel and at leastone channel of content in digital form, including content such as imagecontent, over one communications path for projection by at least oneIPLD in a lighting system. The term “image” is a general term thatrefers to a wide variety of image types, including continuous videoimages such as movies, graphic effects, and news programs, and stillimages such as pictures and clip art. In this way, one or more IPLDs onthe same communications system may be supplied with one or moredifferent channels of image content while at the same time being able torespond to commands, thereby giving the operator of the lighting systemenormous creative control with regard to the image content projected bythe various IPLDs in the system. The term “content” is a general termthat refers to various types of creative works, including image-typeworks and audio works.

One embodiment of the present invention is a lighting system comprisinga central controller, a digital communications path, and a plurality ofimage projection lighting devices. The digital communications pathcomprises a plurality of content transfer channels having respectiveunique content transfer channel addresses and being individuallyselectable in accordance with the content transfer channel addressesthereof. The plurality of image projection lighting devices haverespective unique device addresses and are interconnected by the digitalcommunications path for communicating content on a selected one or moreof the content transfer channels in response to commands from thecentral controller.

Another embodiment of the present invention is a lighting systemcomprising a first digital communications path compliant with a DMXprotocol; a second digital communications path having a bandwidthsufficient for transferring content in digital form; a plurality oflight fixtures interconnected by the first digital communications path,the light fixtures including a plurality of image projection lightingdevices having respective unique device addresses and beinginterconnected by both the first and second digital communicationspaths; and a DMX controller interconnected with the light fixtures bythe first digital communications path. The second digital communicationspath is a bidirectional path comprising a plurality of addressablecontent transfer channels individually selectable by the DMX controllerin accordance with the addresses thereof.

Another embodiment of the present invention is a multiparameter lightcomprising an internal control system, a light valve, an image controlinterface coupling the light valve to the internal control system, and acommunications port coupled to the internal control system. The internalcontrol system comprises a component for recognizing a unique deviceaddress received at the communications port on a control channel, and acomponent for selectively accessing a plurality of content transferchannels having respective unique content transfer channel addresses tocommunicate content in digital form thereon in response to receipt ofthe unique device address and at least one of the content transferchannel addresses at the communications port on the control channel.

Another embodiment of the present invention is a method of controlling alighting system comprising a digital communications path with abandwidth sufficient for communicating a plurality of content signals indigital form on respective transfer channels having respective uniquechannel addresses, and a plurality of image projection lighting devicesinterconnected by the digital communications path and having respectiveunique device addresses. The method comprises selecting a first one ofthe image projection lighting devices by the unique device addressthereof; accessing with the first image projection lighting device afirst one of the transfer channels of the digital communications path bythe unique channel address thereof; carrying a first content signal overthe digital communications path on the first transfer channel during atleast part of the first image projection lighting device accessing step;selecting a second one of the image projection lighting devices by theunique device address thereof; accessing with the second imageprojection lighting device a second one of the transfer channels of thedigital communications path by the unique channel address thereof; andcarrying a second content signal over the digital communications path onthe second transfer channel during at least part of the second imageprojection lighting device accessing step.

A further embodiment of the present invention is a lighting systemcomprising a central controller; an image projection lighting devicecomprising a housing, a light valve contained within the housing, and atleast one communications connector mounted to the housing; and a digitalcommunications path comprising a plurality of content transfer channelshaving respective unique content transfer channel addresses, the digitalcommunications path being coupled to the central controller and furtherbeing coupled to the image projection lighting device via thecommunications connector.

Another embodiment of the present invention is a lighting systemcomprising a central controller; an image projection lighting devicecomprising a housing, a light valve contained within the housing, anexternal video input mounted to the housing, an external audio inputmounted to the housing, and at least one communications connectormounted to the housing; and a digital communications path comprising aplurality of content transfer channels having respective unique contenttransfer channel addresses, the digital communications path beingcoupled to the central controller and further being coupled to the imageprojection lighting device via the communications connector.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a frontal side plan view of a multiparameter light of the IPLDtype showing multiple communications system I/O ports.

FIG. 2 is a side frontal plan view of the multiparameter light of FIG. 1showing multiple communications system I/O ports in accordance with thepresent invention.

FIG. 3 is a schematic drawing of a lighting system.

FIG. 4 is a schematic drawing of the architecture of an image projectionlighting device.

FIG. 5 is a bandwidth allocation diagram.

FIG. 6 is a bandwidth allocation diagram.

DETAILED DESCRIPTION OF THE INVENTION, INCLUDING THE BEST MODE

FIGS. 1 and 2 show an example of an image projection lighting device(“IPLD”) type of multiparameter light fixture that is capable of servingas a node on either one or both of two communications paths of acommunications system. One of the communications paths is a digitalcommunications path that is capable of simultaneously carrying commandsignals as well as two or more channels of content in digital form,including image content for projection by multiple IPLDs. FIG. 1 shows afrontal side view of a camera-equipped multiparameter light fixture 100,and FIG. 2 shows a side frontal view of the camera-equippedmultiparameter light fixture of FIG. 1. In FIGS. 1 and 2, a camera 140is attached to lamp housing 130. The camera 140 may be any desired typeof camera, including cameras sensitive to visible wavelengths as well ascameras sensitive to infrared wavelengths. The lamp housing 130 isrotatably attached to a yoke 120 to enable a tilt movement of the lamphousing 130 and the camera 140. The yoke 120 is in turn rotatablyattached to a base housing 110 to enable a pan movement of the lamphousing 130 and the camera 140. The base housing 110 contains a powersupply and communications and control electronic circuits (not shown). Acontrol panel 116 (FIG. 2) on the base housing 110 contains a displayand various buttons for manually setting a unique device address andcontrolling various other operations of the multiparameter light fixture100. The base housing 110 also includes two communications connectors112 and 114 (FIG. 1) that are part of respective digital communicationsports contained in the light fixture 100. It will be appreciated thatmore than two communications ports may be used if desired, and themultiple ports may include one or more analogue ports if desired. Thedigital communications connector 114 illustratively is part of aconventional DMX512 port that has a digital line-in terminal passingthrough to a digital line-out terminal, and is suitable for connectionto a DMX communications path in the communications system. The digitalcommunications connector 112 illustratively is part of a moderate tohigh bandwidth bidirectional digital port, and is suitable forconnection to a moderate to high bandwidth bi-directional digitalcommunications path such as an Ethernet network. The multiparameterlight fixture 100 also has a power connector (not shown), which isomitted for clarity.

Although the IPLD shown in FIG. 1 has two different types ofcommunications ports and a yoke for pan and tilt, IPLDs generally mayhave only one communications port or may have two or more communicationsports, and may have only a couple of parameters or may have manyparameters. For example, one type of IPLD has the parameters of color,shutter, image, dimming, lamp enable, zoom and focus, but not theparameters of pan and tilt (may not have a yoke mount).

The DMX port is provided in the IPLDs of FIGS. 1 and 2 for compatibilitywith existing installations and to provide a somewhat redundant controlpath, if desired. The DMX port may be eliminated entirely, or adifferent type of port may be provided as desired for redundancy orother purposes.

Other types of multiparameter light fixtures such as, for example, theunitary housing type that uses mirrors to direct the projected light(not shown), may also be equipped for image projection lighting and mayalso be provided with a camera.

While the camera 140 may be integrated with the lamp housing 130 in anydesired manner, and may be independently positionable if desired,preferably the camera 140 is rigidly and securely attached to the lamphousing 130. The camera 140 thereby receives an image from wherever thelamp housing 130 is directed at by the pan and tilt mechanism of themultiparameter light 100. In this way, the light projected by themultiparrameter light and the camera essentially point in the samedirection. Images received by the camera 140 are sent to the controlelectronics located within the base housing 110 of the multiparameterlight fixture 100.

Having a camera mounted on a multiparameter light fixture isadvantageous in may ways. For example, frequently large television showssuch as award shows and the like use many multiparameter lights on thestage set. A broadcasting company may also use several cameras to createseveral camera angles that provide different looks at the stage, forbroadcast purposes. IPLD type of light fixtures also may be mounted atmany locations on the stage set. Some will often be mounted on the stageitself behind the performer. Some lights of the invention will bemounted overhead of the performer while still others are mounted tostage right or left. A camera as a component of a IPLD can produce at oralmost broadcast quality pictures from aspects of the stage where thebroadcast companies television cameras are not located and do not havethe ability to image that particular location or direction. The videocamera may be a block camera type such as those available from SonyBroadcast and Professional of One Sony Drive Park Ridge, N.J. Thecommunications port 112 is connected to a digital communications path(FIG. 3) in the communication system to enable the transfer of images toother IPLDs in the lighting system or to a central controller, as wellas the receipt of images from the other IPLDs in the lighting system orfrom a central controller. The operator of the lighting system mayaddress individual IPLDs from the central controller 380 and choosewhich of many content transfer channels is to be acted upon or projectedby the selected IPLDs.

The multiparameter light 100 is suitable for use in a communicationssystem with other multiparameter lights, which may or may not be IPLDtype, as well as with other types of light fixtures that may or may nothave integrated cameras. The communications system may be single path ormultiple path. A suitable multiple path communications system isdescribed in my U.S. Pat. No. 6,331,756 entitled “Method and Apparatusfor Digital Communications with Multiparameter Light Fixtures,” whichissued Dec. 18, 2001 and hereby is incorporated herein by reference inits entirety.

FIG. 3 shows an illustrative multiple path lighting system 300. Centralcontroller 370 (illustratively a DMX controller of a type well known inthe art, although controllers based on other protocols may be used ifdesired), central controller 380 (illustratively a computer system ortwo or more computer systems linked together), and light fixtures 312,314 and 316 are powered from the power mains over standard buildingelectrical wiring 310. A DMX communications cable 302 is run from theDMX controller 370 to an IPLD 312, which illustratively is an IPLD typemultiparameter light fixture such as the light fixture 100, but whichmay be any other type of IPLD. Additional communication cable segments304 and 306 respectively run to IPLDs 314 and 316. While only threeIPLDs are shown in FIG. 3 for clarity, typically lighting systems mayhave thirty or more light fixtures, including light fixtures that arenot IPLDs. The communication cable segment 308 represents the presenceof additional light fixtures. Communications along the DMXcommunications path is unidirectional, in accordance with one aspect ofthe DMX512 protocol.

FIG. 3 also shows a second central controller 380, illustrative asuitably programmed computer system having a monitor and a systemcabinet. The central controller 380 communicates with the IPLDs 312, 314and 316 over a digital communications path, which preferably is amoderate to high transmission rate digital communications path ornetwork having enhanced performance relative to a standard DMXcommunications path. The enhanced performance communications path overwhich the central controller 380 communicates preferably is capable ofsimultaneously carrying multiple bi-directional channels of content,preferably continuous video content, in digital form. Such channels arereferred to herein as content transfer channels. The enhancedperformance communications path is also capable of simultaneouslycarrying commands that provide operating instructions to the IPLDs 312,314 and 316, in addition to the content transfer channels. For fullduplex operation, a hub or intelligent switch 330 is used, whichindividual bi-directional conductors 320, 322 and 324 being respectivelyrun to the multiparameter light fixtures 312, 314 and 316. The use ofsuch a hub or switch for full duplex communications is well known in thecomputer network arts, and is preferable because full duplex helps tominimize collisions of digital information traveling to and from thevarious light fixtures connected to the enhanced performancecommunications path. For half duplex communication, no such hub orswitch need be used. Generally speaking, the enhanced performancecommunications path may be of any desired type, including, for example,such wired networks as token ring, FDDI ring, star, parallel bus, andserial bus, and such wireless networks as radio frequency (“RF”) andinfrared. Various protocols may be used depending on the type ofnetwork, including, for example, Ethernet, the CEBus (ConsumerElectronics Bus) Standard EIA-600, Bluetooth, and the IEEE 802.11bnetworking standard. Other light fixtures in the lighting system 300,which are represented by the communication cable segment 308, may or maynot be connected to the enhanced performance communications path.

The communications system of FIG. 3 illustratively operates as follows,for an illustrative situation in which the operator desires to have theIPLD 312 project one continuous video and the IPLDs 314 and 316 projecta second continuous video. Illustratively, the first video is a moviethat originates from, for example, a DVD player 340, while the secondvideo is a pleasing dynamic multicolored graphics work generated by acomputer graphics generator 350. The central controller 380 receives therespective video signals from the DVD 340 and graphics generator 350,and processes the video signals for transmission over the enhancedperformance communications path to the IPLD devices 312, 314 and 316.The processing by the central controller 380 may involve compressing thevideo signals in a format such as MPEG (Motion Picture Experts Group),as is well known in the video compression art. A variety of compressiontechniques are well known and are suitable for reducing the bandwidthrequirements of various image types, including video.

Content transfer channels each have an identification scheme or address.The identification scheme is defined as a way for the central processorof the IPLD to recognize a particular content transfer channel from agroup of available content transfer channels available on the enhancedperformance communications path. Examples of suitable address oridentification schemes include a specific digital code such as a streamof bytes identifying the start of the channel, a timed based addresswhen one particular content transfer channel starts sending videoinformation, and the expected order of the content transfer channels.Any scheme by which an IPLD can select one particular content transferchannel from a plurality of content transfer channels is anidentification scheme, and is herein referred to as an “address” forconvenience. A particular IPLD is commanded over the enhancedperformance communications path by commands sent from the centralcontroller 380 to select, for example, content transfer channel 1 fromseveral content transfer channels, and to decode the content transferchannel information and project the resultant image.

Each of the IPLDs 312, 314 and 316 has a unique device identifyingaddress for use with the control channel of the enhanced performancecommunications path. This enables an operator to send operation commandsto a specific IPLD from among many IPLDs. The command set used by thecontrol channel for commanding the IPLDs may include but are not limitedto the following commands: Lamp ON, Lamp OFF, X and Y (pan and tilt)coordinates, color change values, intensity values, request for serviceinformation, lens focus, and lens zoom. The command set may also includecommands for the on board camera, such as zoom, focus, color balance,camera enable and iris. The control channel may have any suitableaddress or identification scheme, including, for example, a defaultaddress, a specific digital code such as a stream of bytes identifyingthe start of the channel, a timed based address when one particularchannel starts sending information, an expected channel ordering, and soforth.

As implemented in FIG. 3, the communications protocol for the enhancedperformance communications path uses an address for each light fixtureto enable a light fixture to be discretely addressed from other lightfixtures on the communications path, and also uses respective addressesfor the several content transfer channels. The communications protocolfor the enhanced performance communications path preferably has severalhundred device addresses available to recognize IPLD devices, sincelarge theatrical events use a large numbers of IPILDs. If abidirectional communications path is used, the central controller 380 isalso assigned an address. One method for controlling image projectionlighting is the following. The operator inputs to the central controller380 which IPLD is to be selected and what command the IPLD is to actupon. Any suitable input may be used, including, for example, a keyboard(not shown), interaction with a user interface (not shown) via atouch-sensitive screen or a mouse, or in any other desired manner. Theaddress and command that was input by the operator is sent upon thecontrol channel to the IPLDs on the enhanced performance communicationspath, and the IPLD with a matching address responds by acting upon thedesired command. If the command is to access a content transfer channelfor projection of an image, then the command contains the address of thedesired content transfer channel. The addressed IPLD identifies thedesired content transfer channel, and then decodes the content transferchannel to acquire and project the image.

The system architecture of an IPLD-type multiparameter light 400 havinga camera 464 contained in a camera housing 460 that is rigidly attachedto a lamp housing 440 is shown in FIG. 4, along with simplified portionsof a communications system to which the IPLD 400 is connected. Thecamera housing 460 is rigidly attached to the lamp housing 440 so thatas the lamp housing 440 is moved, the camera 464 and the light projectedfrom the lamp housing 440 are directed towards the same place. Asdescribed in the context of FIG. 3, the DMX controller 370 is of a typewell known in the art, and the central controller 380 illustratively isa computer system capable of communicating with IPLDs over an enhancedperformance communications path. The DMX controller 370 may be omittedif desired.

The IPLD 400 has separate base and lamp housing sections with respectivehousings 410 and 440. The lamp housing section 440 is capable of pan andtilt relative to the base housing 410 by virtue of yoke (see yoke 120 inFIGS. 1 and 2). The base housing 410 contains an internal control systemformed by, illustratively, a microprocessor 416 (various well knownalternatives include microcontrollers, dedicated logic, and so forth)and a memory 415, a port 411 for the enhanced performance communicationspath, a port 413 for the DMX communications path, a motor controlinterface 418 for interfacing the microprocessor 416 to the motors (notshown) that move the lamp housing section 440 relative to the basehousing 410, a lamp power supply control interface 419 for interfacingthe microprocessor 416 to the lamp power supply 421, an image controlinterface 412 for interfacing the microprocessor 416 to a light valve446, a video control interface 417 for interfacing the microprocessor416 to the camera 464, and an analogue-to-digital (“A/D”) converter 414for interfacing the microprocessor 416 to a microphone 462. Themicrophone 462 illustratively is shown mounted in the camera housing460, but may be mounted in the lamp housing 440 or in any otherconvenient place in the IPLD 400. The lamp housing 440 contains areflector 444, a lamp 445, the light valve 446, a condensing lens 447,filter wheels 442, 449 and 443, an iris diaphragm 450 (motor omitted forclarity), and a focusing lens 451 (motor omitted for clarity). Externalconnectors 422 and 423 (not shown in FIG. 1 or FIG. 2) are provided forexternal audio and video signals, respectively. Various wires are runbetween the base housing 410 and the lamp housing 440 (some wires areomitted for clarity) through a wireway 430, which typically is aflexible conduit or pathway between the bearings used to attach the lamphousing 440 to the base housing 410 on pan and tilt lights. Variousother well known components standard to multiparameter light fixtures,such as various thermal sensors and cooling system components, areomitted from FIG. 4 for clarity.

The communications port 413 has an input to receive the DMXtransmissions from the DMX controller 370. The DMX input typically islooped through an output to pass communications received on the input toa neighboring light fixture (not shown) in the lighting system. Thecommunications port 411 is an I/O port for handling communicationsbetween the central controller 380 and the IPLD 400 over the preferablybi-directional enhanced performance communications path, and mayterminate the connection or act as a pass through depending on thenetworking technology used for the enhanced performance communicationspath. If desired, one may use a priority determining system such as, forexample, the type described in my U.S. Pat. No. 6,331,756 entitled“Method and Apparatus for Digital Communications with MultiparameterLight Fixtures,” which issued Dec. 18, 2001 and which hereby isincorporated herein by reference in its entirety.

If the central controller 380 transmits an address on the controlchannel over the enhanced performance communications path that is thesame as the address of the IPLD 400, the match is recognized by themicroprocessor 416 which then responds to an operational command thatfollows the address on the enhanced performance communications path. Thememory 415 stores the operating system for the microprocessor 416, aswell as various applications programs that are capable of producing ormodifying images. One type of program for producing images is thegraphics program, which generates artistic images using variousalgorithms. An example of a graphics program is the Gforce program,which is available from Andy O'Meara from his Website at the internetaddress http://www.55ware.com/index.html. The memory 415 is any type orcombination of types of memory, including ROM and RAM, implemented inany desired memory technology, including magnetic, electronic oroptical. If desired, the memory 415 may buffer incoming image datareceived from the communications port 411, from the camera 464, or fromthe external video input connector 422 to assist in producing a visuallyerror free signal to the image control interface 412.

The microprocessor 416 acts on commands that are received from thecommunications system to control various parameters of the IPLD 400. Forexample, the microprocessor 416 controls the motors of the IPLD 400through the motor control interface 418, controls power levels and dutycycle of the lamp 445 by controlling the lamp power supply 421 throughthe lamp power supply control interface 419, and to control the lightvalve 446 through the image control interface 412. Commands of this typemay be received over the DMX communications path from the DMX controller370 or over the enhanced performance communications path from thecentral controller 380. Other types of commands not conventionally sentover a DMX communications path may be sent over the enhanced performancecommunications path. For example, the microprocessor 416 may act oncommands that are received over the enhanced performance communicationspath from the central controller 380 to control the camera 464 throughthe video control interface 417.

The microprocessor 416 also receives image data that is transmitted overone or more content transfer channels from the central controller 380 orfrom other IPLDs in the lighting system 400.

The microprocessor 416 also receives video signals from the videocontrol interface 417. The video control interface 417 may include theability to process the video signal in various ways, such as, forexample, by compressing the video received from the camera 464, orsignal compression may be performed in the microprocessor 416. Themicroprocessor 416 may use the camera video in various ways. One way issimply to use the camera video to control the light valve 446 throughthe image control interface 412. Another way is to transmit the cameraimage to any one or more other IPLDs in the lighting system or to thecentral controller 380 by transmitting the addresses of the selectedIPLDs or the central controller 380 over the enhanced performancecommunications path on the control channel via the communications port411, and transmitting the camera video over the enhanced performancecommunications path on one of the content transfer channels via thecommunications port 411. If the camera image is sent to the centralcontroller 380, the central controller 380 may store the camera imagefor later use by any IPLD in the lighting system, or may manipulate theimage in a manner to produce special effects or some pleasing alterationand then stored for later use or returned to the IPLD 400 or sent to anyother IPLD in the lighting system. Any camera image received, stored, ormanipulated by the central controller 380 may also be sent to atelevision network wireless transmitter 360 and transmitted over theairways or via satellite.

Transmitting a camera image from one IPLD (a “source”) to another IPLD(a “recipient”) in the lighting system may be performed by the operatorin various ways, using the central controller 380. The operator mayselect the source or recipient first, depending on the desired effect.The operator selects the source IPLD by, for example, using the keyboardto type in the address of the source IPLD followed by the command tosend its video image to the address of the particular content transferchannel. The operator selects the recipient IPLD by, for example, usingthe keyboard to type in the address of the recipient IPLD followed bythe command to project any image data appearing on the particularcontent transfer channel that has been addressed. Alternatively or inaddition to the projection command sent to the recipient IPLD, therecipient IPLD may be instructed to store any image data appearing onthe particular content transfer channel. A variety of other addressingschemes, including addressing schemes well known in the art, aresuitable for use in transmitting a camera image from one IPLD toanother.

If the IPLD 400 is designated as a recipient IPLD for storage of imagestransmitted on one or more particular content transfer channels, thememory 415 would contain one or more sets of images received over one ormore content transfer channels. These image data are stored andcataloged in the memory 415 of the IPLD 400 in any appropriate manner;for example, by date, time and address received from or by designatedfile names. The date, time and address image that identifies the imagefile may automatically become the identifier of the file when the recordcommand is given from the central controller 380. It is also possiblefor the store command to contain a file name so that the operator canname the image file with the keyboard of the central controller 380 forlater recall from the memory 415.

While the central controller 370 (FIG. 3) may use any desired protocol,preferably the central controller 370 uses the DMX protocol and a DMXcommunications path to maintain compatibility with conventionalmultiparameter lighting systems. The IPLDs 312, 314 and 316 are all onthe DMX communications path. If the operator prefers to use theconventional DMX controller 370 to control image projection from theIPLDs, suitable control command sets are sent using the DMX protocolfrom the DMX controller 370 to operate the IPLDs in the desired manner.However, since the DMX protocol is not specified for the transmission ofcontinuous video, any required application programs and image contentwould have to be available at the IPLD from local memory, in the absenceof the enhanced performance communications path. However, with theenhanced performance communications path present, the various contenttransfer channels may be used to transfer image content among thecentral controller 380 and the various IPLDs in the lighting system forstorage in local memory, so that the image content may later be recalledin response to a control command on the DMX communications path from theDMX controller 370 by first addressing the IPLD to respond to a selectedaddress, and then commanding the IPLD to operate from its internalmemory and project the image content. The DMX controller 370 alsocontrols various other features of the IPLDs 312, 314 and 316, such asXY coordinates for pan and tilt, color, intensity, zoom, focus, videoeffects, camera white balance, camera enable, camera iris, and camerazoom and focus.

It will be appreciated that if all the light fixtures in the lightingsystem are interconnected by the communications path from the centralcontroller 380, all of the functions of the DMX controller 370 as wellas additional functions may be performed by the central controller 380.In this event, the DMX controller 370 and the DMX communications pathmay be omitted from the lighting system.

While image content may be transferred under operator control from thecentral controller 380, the DMX controller 370 may be used to controlthe transfer of image content between the IPLDs in the lighting systemover the enhanced performance communications path in a manner similar tothat described for the central controller 380, even in the absence ofthe central controller 380. The image data transferred between IPLDs canbe projected immediately, stored locally, or both stored and projected,and may even be cataloged if desired. In this way the DMX controller 370with the simpler protocol can still command a show of significantmagnitude.

FIG. 5 shows one distribution of channel addresses for the enhancedperformance communications path. Parts 500 and 502 of the bandwidth aretaken up by two control channels, one of which is an auxiliary channel.The control channel 500 is used to command various operations of theIPLDs. This includes but is not limited to one or more of the followingoperations: supplying IPLD unique device addresses, supplying theaddresses of the various content transfer channels for the IPIDs to use,lamp On, lamp Off, X and Y (pan and tilt) coordinates, color changevalues, intensity values, request for service information, lens focus,lens zoom, and on-board camera commands. The auxiliary channel 502 maycontain control information for light fixtures that may not support thesame protocols as used on the enhanced performance communications path.One example of how the auxiliary control channel 502 may be used is in alighting system having gateway-capable light fixtures, such as describedin U.S. Pat. No. 6,331,756, which hereby is fully incorporated herein byreference thereto. The central controller 380 may originate DMX commandsets for the DMX communications path, but send the commands over theauxiliary channel 502 in a form suitable for the enhanced performancecommunications path. As further described in the aforementioned U.S.Pat. No. 6,331,756, a gateway-capable light fixture, which may also bean IPLD, receives the control information sent on the auxiliary channelon a communications port, decodes and converts it to a DMX protocolsignal, and transmits the DMX protocol signal from a DMX communicationsport. In this way, the IPLD may act as a gateway-capable lightingfixture. This eliminates the need to run additional communication cablesto the location where the other type of lighting fixtures and devicesare located if they are in the vicinity of a IPLD acting as a gateway.The auxiliary channel is capable of transmitting several DMX universes,wherein a DMX universe is a group of 512 channels per universe. Eachuniverse can be identified by an identifier when decoded at the IPLDacting as a gateway.

While FIG. 5 (and FIG. 6) show only one auxiliary channel 502 inaddition to the control channel 500, one or more additional auxiliarychannels may be provided with their own identifying addresses, ifdesired.

An auxiliary channel may carry additionally or separately other types ofinformation, including audio information and low quality imageinformation. Each IPLD may be equipped with a transducer device such asdescribed in my U.S. Pat. No. 6,249,091, which issued Jun. 19, 2001, andhereby is incorporated herein by reference in its entirety. Thetransducer may be a microphone such as the microphone 462 (FIG. 3), andmay send a signal representation of sound waves to an analog-to-digitalconverter 414 (FIG. 3). The digital audio signal from the converter 414is sent to the microprocessor 416, where it can be further processed forvarious purposes. One such purpose to for the microprocessor 416 tomanipulate the digital audio data for use in altering an image at thelight valve 446. As explained more fully in the aforementioned U.S. Pat.No. 6,249,091, various other parameters can be modified by commandsignals contained in an auxiliary channel of the enhanced performancecommunications path of a communications system. Another such purpose isto transmit the digital audio data from the microprocessor 416 throughthe communications port 411 (FIG. 4) to the central controller 380,where it may be stored or used in various ways. Since the IPLDs arelikely to me mounted in various locations around a stage, there are usesfor audio signals in various locations close to performers, theaudience, or specific instruments. For example, the digital audio datareceived at the central controller 380 from the IPLD over the enhancedperformance communications path of the communications system is from aspecific location on the stage. The central controller 380 thenprocesses the audio content to provide or modify operating commands senton the control channel of the enhanced performance communications pathto specific IPLDs based on the audio content. In this way, variousaddressed IPLDs commanded by the central controller 380 may have theirparameters modified based upon the audio received from a specific IPLD.In addition, an external audio source (not shown) may be plugged intothe external audio connector 422 (FIG. 4) so that various parametersincluding an image at the image gate may be modified in accordancetherewith. The external audio input works in the same manner as thetransducer output. The external audio input may be used simultaneouslywith the transducer or an external switch (not shown) may be used toswitch between the transducer 462 and the external input 423 422. It isalso possible to electronically switch between the transducer 462 andthe external audio input 423 422 with an electronic switch as known inthe art that is controlled by the microprocessor 416. The transducer 462and the external audio input 423 422 may be stereo or multichannel asknown in the art. The external audio input may alternatively be adigital audio input. The input connector may be mounted to the housingof the IPLD.

The IPLD may also have at least one external video input such as thevideo input 423 (FIG. 4) mounted to the outside of the base housing 410of the IPLD 400, or in any other convenient place on the IPLD. The videoinput 423 is fed into the video control interface 417, which thatconverts the external video signal to a digital video signal as requiredby the microprocessor 416. Alternatively, the external video input maybe digital, RGB, or any other type of video signal known in the art. Themicroprocessor 416 selects which of the inputs to the video controlinterface 417, the camera 464 or the external video input 423, is to beprocessed, or may select both inputs for processing as a combined image.The external video or combined video may be processed for the purposesdescribed for the video from the camera 464 alone, namely, to be sent tothe image control interface 412 for manipulation of the light valve 446to produce a desired projected image, or to be sent to the centralcontroller 380 or to other IPLDs in the lighting system over a contenttransfer channel on the enhanced performance communications path via theport 411. If sent to the central controller 380, the central controller380 may store the video image, or may further process the video imagefor subsequent use or for immediate transmission back to the originatingIPLD or to other IPLDs in the lighting system.

The microprocessor 416 may be programmed in various ways to processimages, whether received from the camera 464, from the external videoinput 423, any image content (video or graphics) received over anycontent transfer channel, and any image content (video or graphics)stored in the memory 415. The microprocessor 416 in the IPLD 400 may becommanded by the central controller 380 to act upon any of the sourcesof content described above. The IPLD 400 may act upon the variouscontent in a variety of different ways, as by transferring content toanother IPLD over the communications system, or by projecting an imageusing the light valve 446 on a stage or other projection surface.Modifications include but are not limited to rotation of the image,digital zoom, keystone correction, color modification, fading betweenone video content source such as one content transfer channel toanother, and various other special effects.

FIG. 5 also shows four content transfer channels 510, 512, 514 and 516,in addition to the control channel 500 and the auxiliary channel 502.Illustratively, each of the content transfer channels 510, 512, 514 and516 has the same bandwidth. The enhanced performance communications pathalso is allocated unused bandwidth 520, which provides a buffer so thatthe enhanced performance communications path is allowed to degradeslightly without causing loss of data on the control and contenttransfer channels. Degrading of bandwidth can happen from variouscauses, including error checking and collisions as will as long cabledistances.

FIG. 6 shows another allocation of bandwidth to the enhanced performancecommunications path. The control channel 500 and the auxiliary channel502 are allocated as in the allocation of FIG. 5. One of the contenttransfer channels, channel 610, is allocated greater bandwidth than theother content transfer channels 612 and 614, which provides a highquality content transfer channel 610 in addition to the normal qualitycontent transfer channels 612 and 614. High quality often requires theuse of increased bandwidth. More than two quality levels may be providedif desired; for example, the auxiliary channel 502 may be used as a lowquality image channel. The address of the content transfer channel maybe followed by a quality identifier. For example, in FIG. 6 the highquality content transfer channel 610 has the address V01 and the qualityidentifier QH (quality high) so that a receiving device such as thecentral controller 380 or another IPLD can optimize the receivingprocessing of the content transfer channel. The lower quality (lessbandwidth) content transfer channels 612 and 614 respectively have theaddresses V02 and V03 and the quality identifier QM (quality medium)following their addresses. If the auxiliary channel 502 is used forvideo transfer, its address might have the quality identifier QL(quality low). If no video quality identifier is sent the contenttransfer channel may operate at a default quality such as QM.

As can be seen by comparing FIG. 5 and FIG. 6, higher quality videotransferring requires more bandwidth and as such may reduce the numberof content transfer channels available to the enhanced performancecommunications path. However, at certain times it is acceptable tosacrifice the number of available content transfer channels iftransferring a high quality image has the highest priority.

The level of quality established for the various content transferchannels may be dynamically set by the operator. The operator decideswhich of the central controller 380 and the other IPLDs in the lightingsystem are to receive the image content from the source IPLD, and alsodecides on the importance of a particular image content that is intendedto be transmitted. Using the central controller 380, the operator entersusing the keyboard or any other suitable input technique the source IPLDaddress, followed by the address of the content transfer channel to beused for sending the particular image content, followed by a qualityidentifier to indicate the level of quality. Using the centralcontroller 380, the operator enters using the keyboard or any othersuitable input technique the recipient IPLD (or central controller)address or addresses, followed by the address of the content transferchannel to be used for sending the particular image content to therecipient, followed by a quality identifier to indicate the level ofquality.

Preferably, a quality identifier is furnished to both the source andrecipient so that the source may ready the data by preparing theappropriate level of compression, and the recipient may optimize thereceiving process. The part of the communications system under controlof the central controller 380 preferably is designed so that an operatorof the central controller 380 can command all the IPLDs, including whatis being sent on a content transfer channel, what IPLD is projectingfrom what content transfer channel, and what the quality of the video ison the content transfer channel. The quality identifier can happen as aseparate identifier that is sent when the commands are given for theIPLD to select the designated content transfer channel, or it couldautomatically happen by the IPLD just recognizing the bandwidth or otherattributes such as a data stream of the content transfer channel.Preferably, the IPLD receives specific commands that identify thequality of the channel it is about to act upon. The order in which thecommands are given can be varied. For instance, the operator couldaddress an IPLD to receive a particular content transfer channel at aparticular quality level, and to act by projecting that image contentwith no image content yet being transferred on the particular contenttransfer channel. Later the operator could supply from the controlsystem a continuous video signal over that particular content transferchannel, in which event the IPLD would respond as soon as the continuousvideo signal is detected on the particular content transfer channel.

The description of the invention and its applications as set forthherein is illustrative and is not intended to limit the scope of theinvention as set forth in the following claims. Variations andmodifications of the embodiments disclosed herein are possible, andpractical alternatives to and equivalents of the various elements of theembodiments are known to those of ordinary skill in the art. These andother variations and modifications of the embodiments disclosed hereinmay be made without departing from the scope and spirit of theinvention.

What is claimed is:
 1. A lighting system comprising: a centralcontroller; a digital communications path comprising a plurality ofcontent transfer channels having respective unique content transferchannel addresses and being individually selectable in accordance withthe content transfer channel addresses thereof; and a plurality of imageprojection lighting devices having respective unique device addressesand being interconnected by the digital communications path forcommunicating content on a selected one or more of the content transferchannels in response to commands from the central controller.
 2. Thelighting system of claim 1 wherein: the digital communications path isbi-directional and further comprises a control channel; and the centralcontroller is interconnected with the image projection lighting devicesby the digital communications path for communicating device addressesand content transfer channel addresses on the control channel.
 3. Thelighting system of claim 2 wherein the digital communications pathfurther comprises an auxiliary channel accessible to the centralcontroller and to the image projection lighting devices forcommunicating commands and content in digital form.
 4. The lightingsystem of claim 1 further comprising: a DMX controller; and a DMXcommunications path; wherein the image projection lighting devices areadditionally interconnected by the DMX communications path forcommunicating device addresses and content transfer channel addressesthereon.
 5. The lighting system of claim 4 wherein at least one of theimage projection lighting devices is a gateway-capable light fixture. 6.A lighting system comprising: a first digital communications pathcompliant with a DMX protocol; a second digital communications pathhaving a bandwidth sufficient for transferring content in digital form;a plurality of light fixtures interconnected by the first digitalcommunications path, the light fixtures including a plurality of imageprojection lighting devices having respective unique device addressesand being interconnected by both the first and second digitalcommunications paths; and a DMX controller interconnected with the lightfixtures by the first digital communications path; wherein the seconddigital communications path is a bi-directional path comprising aplurality of addressable content transfer channels individuallyselectable by the DMX controller in accordance with the addressesthereof.
 7. The lighting system of claim 6 wherein the second digitalcommunications path further comprises an addressable control channel,the lighting system further comprising an additional central controllerinterconnected with the image projection lighting devices by the seconddigital communications path, wherein the content transfer channels andthe control channel are individually selectable by the additionalcentral controller in accordance with the addresses thereof.
 8. Amultiparameter light comprising: an internal control system; a lightvalve; an image control interface coupling the light valve to theinternal control system; a communications port coupled to the internalcontrol system; wherein the internal control system comprises: acomponent for recognizing a unique device address received at thecommunications port on a control channel; and a component forselectively accessing a plurality of content transfer channels havingrespective unique content transfer channel addresses to communicatecontent in digital form thereon in response to receipt of the uniquedevice address and at least one of the content transfer channeladdresses at the communications port on the control channel.
 9. Themultiparameter light of claim 8 further comprising: a camera; and avideo control interface coupling the camera to the internal controlsystem.
 10. The multiparameter light of claim 8 wherein the componentfor selectively accessing a plurality of content transfer channelscomprises: a component for receiving continuous video signals; and acomponent for transmitting continuous video signals.
 11. A method ofcontrolling a lighting system comprising a digital communications pathwith a bandwidth sufficient for communicating a plurality of contentsignals in digital form on respective transfer channels havingrespective unique channel addresses, and a plurality of image projectionlighting devices interconnected by the digital communications path andhaving respective unique device addresses, the method comprising:selecting a first one of the image projection lighting devices by theunique device address thereof; instructing the first image projectionlighting device to communicate a first content signal on a first one ofthe transfer channels of the digital communications path by the uniquechannel address thereof; selecting a second one of the image projectionlighting devices by the unique device address thereof; and instructingthe second image projection lighting device to communicate a secondcontent signal on a second one of the transfer channels of the digitalcommunications path by the unique channel address thereof.
 12. Themethod of claim 11 further comprising: selecting a third one of theimage projection lighting devices by the unique device address thereof;instructing the third image projection lighting device to communicatethe first content signal on the first transfer channel by the uniquechannel address thereof; selecting a fourth one of the image projectionlighting devices by the unique device address thereof; and instructingthe fourth image projection lighting device to communicate the secondcontent signal on the second transfer channel by the unique channeladdress thereof.
 13. The method of claim 12 further comprising:transmitting the first content signal to the digital communications pathon the first transfer channel with one of the first and third imageprojection lighting devices; receiving the first content signal from thedigital communications path on the first transfer channel with the otherone of the first and third image projection lighting devices;transmitting the second content signal to the digital communicationspath on the second channel with one of the second and fourth imageprojection lighting devices; and receiving the second content signalfrom the digital communications path on the second channel with theother one of the second and fourth image projection lighting devices.14. The method of claim 11 wherein the lighting system further comprisesa central controller interconnected with the image projection lightingdevices by the digital communications path, the method furthercomprising: communicating, with the central controller, the firstcontent signal on the first transfer channel by the unique channeladdress thereof; and communicating, with the central controller, thesecond content signal on the second transfer channel by the uniquechannel address thereof.
 15. The method of claim 11 wherein the lightingsystem further comprises a central controller interconnected with theimage projection lighting devices by the digital communications path,the method further comprising: transmitting the first content signal tothe digital communications path on the first transfer channel with oneof the first image projection lighting device and the centralcontroller; receiving the first content signal from the digitalcommunications path on the first transfer channel with the other one ofthe first image projection lighting device and the central controller;transmitting the second content signal to the digital communicationspath on the second channel with one of the second image projectionlighting device and the central controller; and receiving the secondcontent signal from the digital communications path on the secondchannel with the other one of the second image projection lightingdevice and the central controller.
 16. The method of claim 11 wherein atleast one of the first and second content signals is an audio signal.17. The method of claim 11 wherein at least one of the first and secondcontent signals is a video signal.
 18. The method of claim 11 furthercomprising: acquiring the first content signal from a camera disposedwith the first image projection lighting device, the first contentsignal comprising a video content signal; and transmitting the firstcontent signal to the digital communications path on the first transferchannel with the first image projection lighting device.
 19. The methodof claim 11 further comprising: acquiring the first content signal froman external video input disposed with the first image projectionlighting device, the first content signal comprising a video contentsignal; and transmitting the first content signal to the digitalcommunications path on the first transfer channel with the first imageprojection lighting device.
 20. The method of claim 11 furthercomprising: acquiring the first content signal from a memory of thefirst image projection lighting device, the first content signalcomprising a video content signal; and transmitting the first contentsignal to the digital communications path on the first transfer channelwith the first image projection lighting device.
 21. The method of claim11 further comprising: acquiring the first content signal from amicrophone disposed with the first image projection lighting device, thefirst content signal comprising an audio content signal; andtransmitting the first content signal to the digital communications pathon the first transfer channel with the first image projection lightingdevice.
 22. The method of claim 11 further comprising: acquiring thefirst content signal from an external audio input disposed with thefirst image projection lighting device, the first content signalcomprising an audio content signal; and transmitting the first contentsignal to the digital communications path on the first transfer channelwith the first image projection lighting device.
 23. The method of claim11 wherein: the lighting system further comprises a central controllerinterconnected with the image projection lighting devices by the digitalcommunications path; the bandwidth of the digital communications path isalso sufficient for communicating a command signal on a control channel,the control channel having a unique channel address; and the first imageprojection lighting device selecting step comprises sending a commandsignal from the central controller to the digital communications path onthe control channel by the unique channel address thereof, the commandsignal comprising the unique device address for the first imageprojection lighting device and the unique channel address for the firsttransfer channel.
 24. The method of claim 23 wherein the bandwidth ofthe digital communications path is also sufficient for communicating aquality identifier signal on the command channel, the command signalfurther comprising the quality identifier signal.
 25. The method ofclaim 11 wherein: the lighting system further comprises a DMX controllerinterconnected with the image projection lighting devices by a DMXcommunications path; and the first image projection lighting deviceselecting step comprises sending a DMX command signal from the DMXcontroller to the DMX communications path.
 26. A lighting systemcomprising: a central controller; an image projection lighting devicecomprising a housing, a light valve contained within the housing, and atleast one communications connector mounted to the housing; and a digitalcommunications path comprising a plurality of content transfer channelshaving respective unique content transfer channel addresses, the digitalcommunications path being coupled to the central controller and furtherbeing coupled to the image projection lighting device via thecommunications connector.
 27. The lighting system of claim 26 whereinthe image projection lighting device further comprises at least oneexternal video input mounted to the housing.
 28. The lighting system ofclaim 27 wherein the external video input is analog.
 29. The lightingsystem of claim 27 wherein the external video input is digital.
 30. Alighting system comprising: a central controller; an image projectionlighting device comprising a housing, a light valve contained within thehousing, an external video input mounted to the housing, an externalaudio input mounted to the housing, and at least one communicationsconnector mounted to the housing; and a digital communications pathcomprising a plurality of content transfer channels having respectiveunique content transfer channel addresses, the digital communicationspath being coupled to the central controller and further being coupledto the image projection lighting device via the communicationsconnector.
 31. The lighting system of claim 30 wherein the externalaudio input is analog.
 32. The lighting system of claim 30 wherein theexternal audio input is digital.
 33. A method of controlling a lightingsystem comprising a digital communications path and a plurality of imageprojection lighting devices interconnected by the digital communicationspath, the method comprising: instructing a first one of the imageprojection lighting devices by a first device address to transmit animage-containing signal to the digital communications path, the firstdevice address being unique to the first image projection lightingdevice; and instructing a second one of the image projection lightingdevices by a second device address to receive an image-containing signalfrom the digital communications path, the second device address beingunique to the second image projection lighting device; wherein transferof an image from the first image projection lighting device to thesecond image projection lighting device occurs when the first imageprojection lighting device is transmitting and the second imageprojection lighting device is receiving, regardless of when the firstimage projection lighting device instructing step occurs relative to thesecond image projection lighting device instructing step.
 34. A methodof controlling a lighting system comprising a digital communicationspath and a plurality of image projection lighting devices interconnectedby the digital communications path, the method comprising: transmittingan image-containing signal from a first one of the image projectionlighting devices to the digital communications path, theimage-containing signal containing an image from a source disposed withthe first image projection lighting device; and receiving theimage-containing signal at a second one of the image projection lightingdevices from the digital communications path.
 35. The method of claim 34wherein the source is a memory of the first image projection lightingdevice, further comprising reading the image from the memory fortransmission to the digital communications path.
 36. The method of claim34 wherein the source is a camera disposed with the first imageprojection lighting device, further comprising acquiring the image fromthe camera for transmission to the digital communications path.
 37. Alighting system comprising: a digital communications path having acontrol channel; a plurality of image projection lighting devices havingrespective unique device addresses and being interconnected by thedigital communications path; and a central controller interconnectedwith the image projection lighting devices by the digital communicationspath; wherein at least one of the image projection lighting devicescomprises a camera; and wherein the image projection lighting devicesare individually selectable by their respective device addresses toreceive a camera control signal from the control channel of the digitalcommunications path.
 38. The lighting system of claim 37 wherein thecamera control signal is a camera enable signal, a color balance signal,an iris signal, a focus signal, or a zoom signal.
 39. A method ofcontrolling a lighting system comprising a digital communications path,a central controller, and a plurality of image projection lightingdevices, the central controller and the image projection lightingdevices being interconnected by the digital communications path, themethod comprising: instructing a first one of the image projectionlighting devices by a first device address to transmit animage-containing signal to the digital communications path, the firstdevice address being unique to the first image projection lightingdevice; and enabling the central controller to receive animage-containing signal from the digital communications path; whereintransfer of an image from the first image projection lighting device tothe central controller occurs when the first image projection lightingdevice is transmitting and the central controller is receiving,regardless of when the first image projection lighting deviceinstructing step occurs relative to the central controller instructingstep.
 40. The method of claim 39 further comprising reading the imagefrom a memory of the first image projection lighting device fortransmission to the digital communications path.
 41. The method of claim39 further comprising acquiring the image from a camera disposed withthe first image projection lighting device, for transmission to thedigital communications path.
 42. The method of claim 39 wherein theenabling step comprises instructing the central controller by a seconddevice address to receive an image-containing signal from the digitalcommunications path, the second device address being unique to thecentral controller.
 43. A method of controlling a lighting systemcomprising a digital communications path, a central controller, and aplurality of image projection lighting devices, the central controllerand the image projection lighting devices being interconnected by thedigital communications path, the method comprising: instructing a firstone of the image projection lighting devices by a first device addressto receive a first image-containing signal from the digitalcommunications path, the first device address being unique to the firstimage projection lighting device; instructing a second one of the imageprojection lighting devices by a second device address to receive asecond image-containing signal from the digital communications path, thesecond device address being unique to the second image projectionlighting device; transmitting the first image-containing signal to thedigital communications path from the central controller; andtransmitting the second image-containing signal to the digitalcommunications path from the central controller, wherein transfer of afirst image is enabled after both the first image projection lightingdevice instructing step and the first image-containing signaltransmitting step occur, regardless of the order thereof; and whereintransfer of a second image is enabled after both the second imageprojection lighting device instructing step and the secondimage-containing signal transmitting step occur, regardless of the orderthereof.
 44. A method of controlling a lighting system comprising adigital communications path, a central controller, and a plurality ofimage projection lighting devices, the central controller and the imageprojection lighting devices being interconnected by the digitalcommunications path, the method comprising: transmitting a firstimage-containing signal to the digital communications path from thecentral controller; receiving the first image-containing signal from thedigital communications path at a first one of the image projectionlighting devices based on a first device address, the first deviceaddress being unique to the first image projection lighting device;transmitting a second image-containing signal to the digitalcommunications path from the central controller; and receiving thesecond image-containing signal from the digital communications path at asecond one of the image projection lighting devices based on a seconddevice address, the second device address being unique to the secondimage projection lighting device; wherein transfer of a first imageoccurs after both the first image-containing signal transmitting stepand the first image-containing signal receiving step occur, regardlessof the order thereof; and wherein transfer of a second image occursafter both the second image-containing signal transmitting step and thesecond image-containing receiving step occur, regardless of the orderthereof.
 45. A method of controlling a lighting system comprising adigital communications path, a central controller, and a plurality ofimage projection lighting devices, the central controller and the imageprojection lighting devices being interconnected by the digitalcommunications path, the method comprising: transmitting an instructionfrom the central controller to a first one of the image projectionlighting devices to receive and store an image-containing signal fromthe digital communications path, the instruction including a firstdevice address unique to the first image projection lighting device;receiving the image-containing signal from the digital communicationspath with the first image projection lighting device; and storing animage from the image-containing signal received in the receiving step ina memory of the first image projection lighting device.
 46. The methodof claim 45, further comprising transmitting the image-containing signalfrom the central controller to the digital communications path.
 47. Themethod of claim 45, further comprising transmitting the image-containingsignal from a memory of a second one of the image projection lightingdevices.
 48. The method of claim 45, further comprising transmitting theimage-containing signal from a camera disposed with a second one of theimage projection lighting devices.
 49. A method of controlling alighting system comprising a digital communications path, a centralcontroller, and a plurality of image projection lighting devices, thecentral controller and the image projection lighting devices beinginterconnected by the digital communication path, the method comprising:receiving an image-containing signal from the digital communicationspath with a first one of the image projection lighting devices;transmitting an instruction from the central controller to the firstimage projection lighting device, by a first device address unique tothe first image projection lighting device, to act upon theimage-containing signal from the receiving step; and acting upon theimage-containing signal from the receiving step in accordance with theinstruction from the transmitting step under control of a microprocessorin the first image projection lighting device.
 50. The method of claim49, wherein the acting upon step further comprises transferring an imagein the image-containing signal to a second one of the image projectionlighting devices.
 51. The method of claim 49, wherein the acting uponstep further comprising projecting an image in the image-containingsignal from the first image projection lighting device.
 52. The methodof claim 49, wherein the acting upon step further comprises modifying animage in the image-containing signal.
 53. The method of claim 49:further comprising receiving an additional image-containing signal fromthe digital communications path with the first image projection lightingdevices; wherein the acting upon step further comprises fading from animage in the image-containing signal to another image in the additionalimage-containing signal.
 54. A method of controlling a lighting systemcomprising a digital communications path, a central controller, and aplurality of image projection lighting devices, the central controllerand the image projection lighting devices being interconnected by thedigital communications path, the method comprising: selecting a channelbandwidth from among a plurality of channel bandwidths to establish alevel of image quality; transmitting an instruction from the centralcontroller to a first one of the image projection lighting devices by afirst device address to receive an image-containing signal at theselected bandwidth from the digital communications path, the firstdevice address being unique to the first image projection lightingdevice; and transmitting the image-containing signal to the digitalcommunications path at no greater than the selected bandwidth.
 55. Animage projection lighting device comprising: a base section; a lampsection coupled to the base section for motorized pan and tilt movementrelative thereto, the lamp section comprising: a lamp; a light valvedisposed along a light path from the lamp; and a projection lensdisposed along the light path; an external digital video signal inputfor receiving an external digital video signal; an internal digitalvideo memory source for storing an internal digital video signal; and acontrol system coupled to the external digital video signal input, theinternal digital video memory source, and the light valve formanipulating the light valve in accordance with the external digitalvideo signal and the internal digital video signal.
 56. The imageprojection lighting device of claim 55 wherein the control systemcomprises means for compressing the external digital video signal. 57.The image projection lighting device of claim 55 wherein the externaldigital video signal is for producing a first image, and the internaldigital video signal is for producing a second image, the first imageand the second image being a same image.
 58. The image projectionlighting device of claim 55 wherein the external digital video signal isfor producing a first image, the internal digital video signal is forproducing a second image, the first image and the second image beingdifferent images.
 59. The image projection lighting device of claim 55further comprising a camera having a camera video output; wherein thecontrol system is coupled to the camera for manipulating the light valvein accordance with a camera video signal from the camera video output.60. The image projection lighting device of claim 59 wherein the controlsystem comprises means for compressing the camera video signal.
 61. Theimage projection lighting device of claim 59 wherein the control systemcomprises means for manipulating the light valve in accordance with boththe external digital video signal and the camera video signal to producea combined projected image.
 62. The image projection light device ofclaim 59 wherein the control system comprises: a video interface coupledto the external digital video signal input and the camera video outputfor receiving the external digital video signal and the camera videosignal respectively; a microprocessor for issuing light valve controlsignals in response to the external digital video signal received at theexternal digital video signal input, and the camera video signal at thecamera video output; and an image interface coupled to the light valvefor controlling the light valve in response to the light valve controlsignals from the microprocessor.
 63. The image projection lightingdevice of claim 55 further comprising an image control, the externaldigital video signal being sent to the image control for manipulation ofthe light valve.